ACUS48 KWNS 230959
SWOD48
SPC AC 230957

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CST Sat Nov 23 2019

Valid 261200Z - 011200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5...
A powerful 110 to 130 kt mid-level jet is forecast to move quickly
east-northeastward across the south-central U.S. on Tuesday and into
the eastern states on Wednesday. Strong moisture advection is
forecast ahead of the associated upper-level trough. In response a
moist airmass should be in place across the Lower Mississippi Valley
by midday on Tuesday. Thunderstorms will be possible on Tuesday from
southeast Texas eastward into Mississippi as the upper-level trough
moves through the southern and central Plains. An isolated severe
threat may develop across parts of the central Gulf Coast where
instability is forecast to be the greatest. The upper-level trough
is forecast to move quickly east-northeastward away from the moist
airmass on Wednesday but thunderstorms will still be possible along
a cold front moving eastward through the southeastern states. An
isolated severe threat can not be ruled out in the eastern Gulf
Coast states mainly early in the period on Wednesday.

...Thursday/Day 6 to Saturday/Day 8...
On Thursday, the medium-range models move an upper-level ridge
across the central U.S. and move an upper-level low to the West
Coast. On Friday, both the ECMWF and GFS move the upper-level low
into the Intermountain West and strengthen southwest mid-level flow
across the Great Plains. Thunderstorms would be possible in the
southern PLains as a moist airmass advects northward across the
region. This potential for thunderstorm development would continue
into Saturday in the south-central states as the upper-level trough
moves northeastward across the Rockies. A severe threat would be
possible both Friday and Saturday in the southern Plains but would
be dependent upon the strength of moisture return and instability.
Due to the extended range and uncertainty on the timing of the
upper-level system, predictability is low on Friday and Saturday.

..Broyles.. 11/23/2019